Borgoth, The Lost Demon is a unique Oppressor in Act V of Diablo III. He is found in the Realm of the Banished accessed through the Realmwalker in the Battlefields of Eternity. Unlike other Oppressors, Borgoth is modeled after Izual.
In combat, he has the Desecrator, Waller, Vortex and Missile Dampening traits.
A bounty may be offered to kill Borgoth, in which case the secondary objective is to kill 50 enemies.